This invention relates to pipe systems, and in particular, to an indicator for ensuring the presence of a sealing gasket in a pipe system, after installation of the system. While the invention is described with particular application in regard to plastic sewer main pipe systems, those skilled in the art will recognize the wider applicability of the inventive principles discussed hereinafter.
Plastic sewer pipe material is available on the market which provides low-cost and easy to install sewer systems. Commonly, the pipe is made in a variety of internal diameter sizes from a suitable polyvinylchloride material or other plastic materials. In one commercially available system, the pipes have a first tapered end, and a second end having an integrally formed bell for receiving the tapered end of the succeeding pipe. The bell has a receptacle, race or groove formed in it, which receives a rubber gasket. When the gasket is properly inserted, the system is an excellent one for a variety of fluid handling applications.
Most local ordinances and building codes prohibit pollution of the soil and water table by unwanted ground and waste water eminating from the sanitary sewer pipe system. Infiltration of surface water within the sanitary sewer system also is undesirable because it overloads sewage treatment plants.
Plastic pipe systems with suitable rubber gaskets are quite capable of preventing both infiltration and exfiltration with respect of the pipe system, provided the gaskets are properly positioned and used. Plastic pipe systems have not achieved their commercial potential for sewage systems, however, because no check was available, prior to my invention, for ensuring the presence of the gasket once the pipe system is installed without costly testing procedures. Plastic pipes normally are opaque. The pipe sections and the gaskets are supplied separately. Consequently, if the field installer decided not to include the gasket in all or part of the system, or if the gasket had been pushed from the gasket race during installation, an inspector attempting to oversee proper installation can not ensure gasket presence by visual inspection. Plastic pipe sewer main sales have suffered as a result of this difficulty.
The invention disclosed hereinafter overcomes this deficiency by providing a quick and inexpensive means for visually inspecting and ensuring the proper placement of gaskets in plastic pipe systems, not only for the benefit of the inspector, but for the installer who wants to be certain of a good installation.
Various means for tagging a gasket in pipe systems are known in the prior art. In general, the prior art devices, while similar in function, are not adaptable to plastic pipe use because of the interconnection form used for joining plastic pipe sections. Plastic pipe is interconnected by sliding one pipe section within another for a relatively long distance. There are no flange joints commonly used in pipe systems constructed from other material. In addition, prior art indicating arrangements generally are expensive to implement, which tends to overcome the cost advantage of plastic pipe systems.
One of the objects of this invention is to provide a low cost device for indicating the presence of a gasket in a pipe seal.
Another object of this invention is to provide means for aiding in proper placement of a gasket.
Another object of this invention is to provide an easy to manufacture gasket present indicating means.
Other objects will be apparent to those skilled in the art in light of the following description and accompanying drawings.